Patel Ritesh Pravinbahi1*,Ganatra Amit Pravinchandra1

Transmission control protocol have gone through various revisions to develop new method of responding to network congestion control as per past, present and future requirements. In cloud computing moving large size of a VM from one data center to another data center over WAN is a challenging task. To regulate data flow, sending of data is carried out in three phases iteratively. Slow start, congestion avoidance and fast recovery. All these methods are functions of ACK reception. Specially in slow start, initially it is very slow but it progresses aggressively as times increases. Because of a slow start, it suffers from low network resource utilization in the high bandwidth delay scenario. At every receipt of ack, the congestion window is either step up by one or a zero. In this paper, efforts are made to improve slow start behavior by changing step up count (scnt) to improve network resource utilization. Experiments and results, observed during the slow start phase, show that throughput has increased to 51.23%, time to reach epoch has reduced to 40%, the position of epoch point has increased to 4 times higher than traditional but it leads to increased 30% of packet drops.